import Foundation
import UIKit
import SwiftSignalKit
import AsyncDisplayKit
import Display
import Postbox
import TelegramCore
import TelegramPresentationData
import AccountContext
import ComponentFlow
import MultilineTextComponent
import BalancedTextComponent
import TextFieldComponent
import ComponentDisplayAdapters
import TextFormat

private final class FactCheckAlertContentNode: AlertContentNode {
    private let context: AccountContext
    private var theme: AlertControllerTheme
    private var presentationTheme: PresentationTheme
    private let strings: PresentationStrings
    private let text: String
    private let initialValue: String

    private let titleView = ComponentView<Empty>()
    
    private let state = ComponentState()
    
    private let inputBackgroundNode = ASImageNode()
    private let inputField = ComponentView<Empty>()
    private let inputFieldExternalState = TextFieldComponent.ExternalState()
    private let inputPlaceholderView = ComponentView<Empty>()
    
    private let actionNodesSeparator: ASDisplayNode
    private let actionNodes: [TextAlertContentActionNode]
    private let actionVerticalSeparators: [ASDisplayNode]
    
    private let disposable = MetaDisposable()
    
    private var validLayout: CGSize?
    
    private let hapticFeedback = HapticFeedback()
    
    var present: (ViewController) -> () = { _ in }
    
    var complete: (() -> Void)? {
        didSet {
//            self.inputFieldNode.complete = self.complete
        }
    }
    
    override var dismissOnOutsideTap: Bool {
        return self.isUserInteractionEnabled
    }
    
    init(context: AccountContext, theme: AlertControllerTheme, presentationTheme: PresentationTheme, strings: PresentationStrings, actions: [TextAlertAction], text: String, value: String, entities: [MessageTextEntity]) {
        self.context = context
        self.theme = theme
        self.presentationTheme = presentationTheme
        self.strings = strings
        self.text = text
        self.initialValue = value
        
        if !value.isEmpty {
            self.inputFieldExternalState.initialText = chatInputStateStringWithAppliedEntities(value, entities: entities)
        }
        
        self.actionNodesSeparator = ASDisplayNode()
        self.actionNodesSeparator.isLayerBacked = true
        
        self.actionNodes = actions.map { action -> TextAlertContentActionNode in
            return TextAlertContentActionNode(theme: theme, action: action)
        }
        
        var actionVerticalSeparators: [ASDisplayNode] = []
        if actions.count > 1 {
            for _ in 0 ..< actions.count - 1 {
                let separatorNode = ASDisplayNode()
                separatorNode.isLayerBacked = true
                actionVerticalSeparators.append(separatorNode)
            }
        }
        self.actionVerticalSeparators = actionVerticalSeparators
        
        super.init()
        
        self.inputBackgroundNode.displaysAsynchronously = false
        self.inputBackgroundNode.image = generateStretchableFilledCircleImage(diameter: 16.0, color: presentationTheme.actionSheet.inputHollowBackgroundColor, strokeColor: presentationTheme.actionSheet.inputBorderColor, strokeWidth: UIScreenPixel)
        
        self.addSubnode(self.actionNodesSeparator)
        self.addSubnode(self.inputBackgroundNode)
        
        for actionNode in self.actionNodes {
            self.addSubnode(actionNode)
        }
        self.actionNodes.last?.actionEnabled = true
        
        for separatorNode in self.actionVerticalSeparators {
            self.addSubnode(separatorNode)
        }
                
        self.updateTheme(theme)
        
        self.state._updated = { [weak self] transition, _ in
            guard let self, let _ = self.validLayout else {
                return
            }
            self.requestLayout?(transition.containedViewLayoutTransition)
        }
    }
    
    deinit {
        self.disposable.dispose()
    }
    
    var textAndEntities: (String, [MessageTextEntity]) {
        let text = self.inputFieldExternalState.text.string
        let entities = generateChatInputTextEntities(self.inputFieldExternalState.text)
        return (text, entities)
    }

    override func updateTheme(_ theme: AlertControllerTheme) {
        self.theme = theme
        
        self.actionNodesSeparator.backgroundColor = theme.separatorColor
        for actionNode in self.actionNodes {
            actionNode.updateTheme(theme)
        }
        for separatorNode in self.actionVerticalSeparators {
            separatorNode.backgroundColor = theme.separatorColor
        }
        
        if let size = self.validLayout {
            _ = self.updateLayout(size: size, transition: .immediate)
        }
    }
    
    override func updateLayout(size: CGSize, transition: ContainedViewLayoutTransition) -> CGSize {
        var size = size
        size.width = min(size.width, 270.0)
        let measureSize = CGSize(width: size.width - 16.0 * 2.0, height: CGFloat.greatestFiniteMagnitude)
        
        let hadValidLayout = self.validLayout != nil
        
        self.validLayout = size
        
        var origin: CGPoint = CGPoint(x: 0.0, y: 16.0)
        let spacing: CGFloat = 5.0
        
        
        let titleSize = self.titleView.update(
            transition: .immediate,
            component: AnyComponent(MultilineTextComponent(
                text: .plain(NSAttributedString(string: self.text, font: Font.semibold(17.0), textColor: self.theme.primaryColor)),
                horizontalAlignment: .center,
                maximumNumberOfLines: 0
            )),
            environment: {},
            containerSize: CGSize(width: measureSize.width, height: 1000.0)
        )
        let titleFrame = CGRect(origin: CGPoint(x: floor((size.width - titleSize.width) * 0.5), y: origin.y), size: titleSize)
        if let titleComponentView = self.titleView.view {
            if titleComponentView.superview == nil {
                self.view.addSubview(titleComponentView)
            }
            titleComponentView.frame = titleFrame
        }
        origin.y += titleSize.height + 17.0
        
        let actionButtonHeight: CGFloat = 44.0
        var minActionsWidth: CGFloat = 0.0
        let maxActionWidth: CGFloat = floor(size.width / CGFloat(self.actionNodes.count))
        let actionTitleInsets: CGFloat = 8.0
        
        var effectiveActionLayout = TextAlertContentActionLayout.horizontal
        for actionNode in self.actionNodes {
            let actionTitleSize = actionNode.titleNode.updateLayout(CGSize(width: maxActionWidth, height: actionButtonHeight))
            if case .horizontal = effectiveActionLayout, actionTitleSize.height > actionButtonHeight * 0.6667 {
                effectiveActionLayout = .vertical
            }
            switch effectiveActionLayout {
                case .horizontal:
                    minActionsWidth += actionTitleSize.width + actionTitleInsets
                case .vertical:
                    minActionsWidth = max(minActionsWidth, actionTitleSize.width + actionTitleInsets)
            }
        }
        
        let insets = UIEdgeInsets(top: 18.0, left: 18.0, bottom: 9.0, right: 18.0)
        
        var contentWidth = max(titleSize.width, minActionsWidth)
        contentWidth = max(contentWidth, 234.0)
        
        var actionsHeight: CGFloat = 0.0
        switch effectiveActionLayout {
            case .horizontal:
                actionsHeight = actionButtonHeight
            case .vertical:
                actionsHeight = actionButtonHeight * CGFloat(self.actionNodes.count)
        }
        
        let resultWidth = contentWidth + insets.left + insets.right
        
        let inputInset: CGFloat = 16.0
        let inputWidth = resultWidth - inputInset * 2.0
        
        var characterLimit: Int = 1024
        if let data = self.context.currentAppConfiguration.with({ $0 }).data, let value = data["factcheck_length_limit"] as? Double {
            characterLimit = Int(value)
        }
        
        let inputFieldSize = self.inputField.update(
            transition: .immediate,
            component: AnyComponent(TextFieldComponent(
                context: self.context,
                theme: self.presentationTheme,
                strings: self.strings,
                externalState: self.inputFieldExternalState,
                fontSize: 14.0,
                textColor: self.presentationTheme.actionSheet.inputTextColor,
                accentColor: self.presentationTheme.actionSheet.controlAccentColor,
                insets: UIEdgeInsets(top: 8.0, left: 2.0, bottom: 8.0, right: 2.0),
                hideKeyboard: false,
                customInputView: nil,
                resetText: nil,
                isOneLineWhenUnfocused: false,
                characterLimit: characterLimit,
                emptyLineHandling: .oneConsecutive,
                formatMenuAvailability: .available([.bold, .italic, .link]),
                returnKeyType: .default,
                lockedFormatAction: {
                },
                present: { [weak self] c in
                    self?.present(c)
                },
                paste: { _ in
                },
                returnKeyAction: nil,
                backspaceKeyAction: nil
            )),
            environment: {},
            containerSize: CGSize(width: inputWidth, height: 270.0)
        )
        self.inputField.parentState = self.state
        let inputFieldFrame = CGRect(origin: CGPoint(x: inputInset, y: origin.y), size: inputFieldSize)
        if let inputFieldView = self.inputField.view as? TextFieldComponent.View {
            if inputFieldView.superview == nil {
                self.view.addSubview(inputFieldView)
            }
            transition.updateFrame(view: inputFieldView, frame: inputFieldFrame)
            transition.updateFrame(node: self.inputBackgroundNode, frame: inputFieldFrame)
            
            if !hadValidLayout {
                inputFieldView.activateInput()
            }
        }
        
        let inputPlaceholderSize = self.inputPlaceholderView.update(
            transition: .immediate,
            component: AnyComponent(
                MultilineTextComponent(text: .plain(NSAttributedString(
                    string: self.strings.FactCheck_Placeholder,
                    font: Font.regular(14.0),
                    textColor: self.presentationTheme.actionSheet.inputPlaceholderColor
                )))
            ),
            environment: {},
            containerSize: CGSize(width: inputWidth, height: 240.0)
        )
        let inputPlaceholderFrame = CGRect(origin: CGPoint(x: inputInset + 10.0, y: floorToScreenPixels(inputFieldFrame.midY - inputPlaceholderSize.height / 2.0)), size: inputPlaceholderSize)
        if let inputPlaceholderView = self.inputPlaceholderView.view {
            if inputPlaceholderView.superview == nil {
                inputPlaceholderView.isUserInteractionEnabled = false
                self.view.addSubview(inputPlaceholderView)
            }
            inputPlaceholderView.frame = inputPlaceholderFrame
            inputPlaceholderView.isHidden = self.inputFieldExternalState.hasText
        }
        
        if let lastActionNode = self.actionNodes.last {
            if self.initialValue.isEmpty {
                lastActionNode.actionEnabled = self.inputFieldExternalState.hasText
            } else {
                if self.inputFieldExternalState.hasText {
                    lastActionNode.action = TextAlertAction(
                        type: .defaultAction,
                        title: self.strings.Common_Done,
                        action: lastActionNode.action.action
                    )
                } else {
                    lastActionNode.action = TextAlertAction(
                        type: .defaultDestructiveAction,
                        title: self.strings.FactCheck_Remove,
                        action: lastActionNode.action.action
                    )
                }
            }
        }
                        
        let resultSize = CGSize(width: resultWidth, height: titleSize.height + spacing + inputFieldSize.height + 17.0 + actionsHeight + insets.top + insets.bottom)
        
        transition.updateFrame(node: self.actionNodesSeparator, frame: CGRect(origin: CGPoint(x: 0.0, y: resultSize.height - actionsHeight - UIScreenPixel), size: CGSize(width: resultSize.width, height: UIScreenPixel)))
        
        var actionOffset: CGFloat = 0.0
        let actionWidth: CGFloat = floor(resultSize.width / CGFloat(self.actionNodes.count))
        var separatorIndex = -1
        var nodeIndex = 0
        for actionNode in self.actionNodes {
            if separatorIndex >= 0 {
                let separatorNode = self.actionVerticalSeparators[separatorIndex]
                switch effectiveActionLayout {
                    case .horizontal:
                        transition.updateFrame(node: separatorNode, frame: CGRect(origin: CGPoint(x: actionOffset - UIScreenPixel, y: resultSize.height - actionsHeight), size: CGSize(width: UIScreenPixel, height: actionsHeight - UIScreenPixel)))
                    case .vertical:
                        transition.updateFrame(node: separatorNode, frame: CGRect(origin: CGPoint(x: 0.0, y: resultSize.height - actionsHeight + actionOffset - UIScreenPixel), size: CGSize(width: resultSize.width, height: UIScreenPixel)))
                }
            }
            separatorIndex += 1
            
            let currentActionWidth: CGFloat
            switch effectiveActionLayout {
                case .horizontal:
                    if nodeIndex == self.actionNodes.count - 1 {
                        currentActionWidth = resultSize.width - actionOffset
                    } else {
                        currentActionWidth = actionWidth
                    }
                case .vertical:
                    currentActionWidth = resultSize.width
            }
            
            let actionNodeFrame: CGRect
            switch effectiveActionLayout {
                case .horizontal:
                    actionNodeFrame = CGRect(origin: CGPoint(x: actionOffset, y: resultSize.height - actionsHeight), size: CGSize(width: currentActionWidth, height: actionButtonHeight))
                    actionOffset += currentActionWidth
                case .vertical:
                    actionNodeFrame = CGRect(origin: CGPoint(x: 0.0, y: resultSize.height - actionsHeight + actionOffset), size: CGSize(width: currentActionWidth, height: actionButtonHeight))
                    actionOffset += actionButtonHeight
            }
            
            transition.updateFrame(node: actionNode, frame: actionNodeFrame)
            
            nodeIndex += 1
        }
        
        return resultSize
    }
    
    func deactivateInput() {
        if let inputFieldView = self.inputField.view as? TextFieldComponent.View {
            inputFieldView.deactivateInput()
        }
    }
    
    func animateError() {
        if let inputFieldView = self.inputField.view as? TextFieldComponent.View {
            inputFieldView.layer.addShakeAnimation()
        }

        self.hapticFeedback.error()
    }
}

public func factCheckAlertController(context: AccountContext, updatedPresentationData: (initial: PresentationData, signal: Signal<PresentationData, NoError>)? = nil, value: String, entities: [MessageTextEntity], apply: @escaping (String, [MessageTextEntity]) -> Void) -> AlertController {
    let presentationData = updatedPresentationData?.initial ?? context.sharedContext.currentPresentationData.with { $0 }
    
    var dismissImpl: ((Bool) -> Void)?
    var applyImpl: (() -> Void)?
    
    let actions: [TextAlertAction] = [TextAlertAction(type: .genericAction, title: presentationData.strings.Common_Cancel, action: {
        dismissImpl?(true)
    }), TextAlertAction(type: .defaultAction, title: presentationData.strings.Common_Done, action: {
        dismissImpl?(true)
        applyImpl?()
    })]
    
    let contentNode = FactCheckAlertContentNode(context: context, theme: AlertControllerTheme(presentationData: presentationData), presentationTheme: presentationData.theme, strings: presentationData.strings, actions: actions, text: presentationData.strings.FactCheck_Title, value: value, entities: entities)
    contentNode.complete = {
        applyImpl?()
    }
    applyImpl = { [weak contentNode] in
        guard let contentNode = contentNode else {
            return
        }
        let (text, entities) = contentNode.textAndEntities
        apply(text, entities)
    }
    
    let controller = AlertController(theme: AlertControllerTheme(presentationData: presentationData), contentNode: contentNode)
    let presentationDataDisposable = (updatedPresentationData?.signal ?? context.sharedContext.presentationData).start(next: { [weak controller] presentationData in
        controller?.theme = AlertControllerTheme(presentationData: presentationData)
    })
    controller.dismissed = { _ in
        presentationDataDisposable.dispose()
    }
    dismissImpl = { [weak controller] animated in
        contentNode.deactivateInput()
        if animated {
            controller?.dismissAnimated()
        } else {
            controller?.dismiss()
        }
    }
    
    contentNode.present = { [weak controller] c in
        controller?.present(c, in: .window(.root))
    }
    
    return controller
}
